| Exam Board | OCR |
|---|---|
| Module | C1 (Core Mathematics 1) |
| Year | 2010 |
| Session | January |
| Marks | 7 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Solving quadratics and applications |
| Type | Quadratic in x^(1/2) - substitution u = √x |
| Difficulty | Standard +0.3 This is a straightforward substitution question where students let u = √x to obtain a quadratic, then solve and back-substitute. While it requires multiple steps and careful algebraic manipulation to express answers in the required surd form, it follows a standard technique taught explicitly in C1 with no novel problem-solving required, making it slightly easier than average. |
| Spec | 1.02b Surds: manipulation and rationalising denominators1.02f Solve quadratic equations: including in a function of unknown |
5 Solve the equation $x - 8 \sqrt { x } + 13 = 0$, giving your answers in the form $p \pm q \sqrt { r }$, where $p , q$ and $r$ are integers.
\hfill \mbox{\textit{OCR C1 2010 Q5 [7]}}